Caesar Cipher

cryptography/caesar-cipher/README.md

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+#Caesar Cipher
+
+The [Caesar Cipher](https://en.wikipedia.org/wiki/Caesar_cipher) is a very simple and common encryption method which does not appear often in full-fledged CTFs but is a good basis for cryptography.
+
+A Caesar Cipher is the shift of a string of letters a certain number of positions down the alphabet.
+
+###Example
+
+Let's say we want to encrypt the string `hello world` to give to our right-handed friend whose favorite number is 3. We will shift our string **left 3**.
+
+Taking the first letter `h`, going 3 places up the alphabet(as it is a left shift) we reach the letter `e`, and so replace it in our string.
+
+Doing so for the whole string creates a jumbled mess of incomprehensible letters unless the reader has the propper decryption shift:
+
+Original: `hello world`
+Final: `ebiil tloia`
+
+To give this to our friend, we would send him the final string with the instructions **right 3**, and either by hand, with a website, or with a script, he would be able to extract our extremely important message.
+
+##Detection
+
+Caesar ciphers are usually presented as very low-point tasks, and can be easy to detect and check for. Strings containing only letters which seem incomprehensibly jumbled can be Caesar ciphers and should be checked.
+
+##Solution
+
+There are many approaches to cracking Caesar ciphers, but most commonly the best way to solve them is to write a script or run the string through a website (Options presented below) which will print out all the possible shifts of a string. At that point the most comprehensible and logical solution can be printed.
+
+##Sources/See More
+
+[Wikipedia and Caesar Ciphers](https://en.wikipedia.org/wiki/Caesar_cipher)
+[Quick and Simple Decryption Tool](https://www.xarg.org/tools/caesar-cipher)